A novel, simple and facile layer by layer (LBL) approach is used for modification of glassy carbon (GC) electrode with multilayer of catalase and nanocomposite containing 1-(3-Aminopropyl)-3-methylimidazolium bromide (amine terminated ionic liquid (NH2-IL)) and titanium nitride nanoparticles (TiNnp). First a thin layer of NH2-IL is covalently attached to GC/TiNnp electrode using electro-oxidation method. Then, with alternative self assemble positively charged NH2-IL and negatively charged catalase a sensitive H2O2biosensor is constructed, whose response is directly correlated to the number of bilay-ers. The surface coverage of active catalase per bilayer, heterogeneous electron transfer rate constant (ks) and Michaelis–Menten constant (KM) of immobilized catalase were 3.32 × 10−12 mol cm−2, 5.28 s−1 and 1.1 mM, respectively. The biosensor shows good stability, high reproducibility, long life-time, and fast amperometric response with the high sensitivity of 380 A mM−1cm- 2 .and low detection limit of 100 nM at concentration range up to 2.1 mM